可卡因诱导不同年龄段大鼠生精细胞凋亡及Caspase-3活性研究

The study of Cocaine induced apoptosis and effection on caspase-3 activeity in germ cells different age rat

目的 探讨可卡因对不同年龄段大鼠生精细胞凋亡的影响。方法 应用 3周、6周和 12周龄S D雄性大鼠皮下注射可卡因 2 8d制造吸毒动物模型。采用放射免疫法测定血清LH、FSH、PRL、T、E2 浓度 ,DNA片段和流式细胞术分析生殖细胞凋亡状况 ,Caspase 3活性。 结果 可卡因诱导 2周后 ,3周龄大鼠睾丸重量减轻 (P <0 .0 5 ) ,体重及其他生殖器官重量无明显影响 ;6周龄大鼠体重、睾丸、附睾和阴茎重量减轻 (P <0 .0 1) ;12周龄大鼠体重和生殖器官重量则均无明显影响 (P >0 .0 5 )。 3周龄实验组大鼠T降低 ,E2 升高 ,差异有显著意义 (P <0 .0 5 ) ,LH、FSH和PRL无明显差异 ;6周龄实验组大鼠LH和T明显降低 ,FSH明显升高 (P <0 .0 5 ) ,而PRL和E2变化 ;12周龄实验组大鼠PRL有明显降低 (P <0 .0 1) ,余无显著差异。 3个年龄段实验组大鼠均出现细胞凋亡梯带 ,其中 6周龄组最为典型。 3周龄和 6周龄实验大鼠生精细胞凋亡峰值明显增高。S期细胞数明显下降 ,其中尤以 6周龄大鼠显著。 3周龄、6周龄和 12周龄实验组大鼠睾丸生精细胞Caspase 3活性均较对照组明显增高 ,其中6周龄实验组Caspase 3活性增高更为明显 (P <0 .0 1)。 结论 可卡因诱导 2 8天可致大鼠生殖器官发育和生殖内分泌功能损害 ,造成生精细胞凋亡增加 。

Objective To study the effect of Cocaine on germ cells apoptosis of male rats in different age.Methods Three weeks old,six weeks old and twelve weeks old male Sprague Dawley rats were given Cocaine hydrochloride(15 mg/kg body weight) subcutaneously daily for four weeks.The serum levels of LH,FSH,PRL,T,E 2 were measured in all rats and DNA fragmentation of germ cells was also determined by gel eletronphoresis.The apoptosis and caspase 3 activity of germ cells were tested by flow cytometry.Results After four weeks of treatment with Cocaine,the weight of testis in three weeks old rats and the weight of body,testis,epididymis and penis in six week old rats were decreased significantly,compared to those of control groups( P < 0.05 ).Compared to the control groups,the serum level of T was decreased significantly in three weeks old and six weeks old male rats,and the serum level of PRL was decreased significantly in twelve weeks old male rats also( P <0.05).In all three groups,the DNA isolated from the Cocaine treated testis displayed clear ladder pattern,especially in six weeks old male rats.The number of apoptosis significantly increased in three weeks old and six weeks old male rats treated with Cocaine( P <0.05).The caspase 3 activity in all three groups given Cocaine increased significantly,especially in 6 weeks old rats,compared to the controls ( P < 0.05 ).Conclusions Cocaine exposure for 4 weeks can lead to significant apoptosis in rat testes in different age,especially in six weeks old rats,and the increase of caspase 3 activity may be the one of key pathway related to the induction of apopsis in testes.